Alert archive / Wisconsin / Flash Flood Warnings in 2011

Flash Flood Warning 13, NWS La Crosse, WI

July 19, 2011Clark County, Wisconsin

NWS La Crosse, WI issued this flash flood warning at Jul 19, 2011, 9:41 PM CDT for Clark County, Wisconsin. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 19, 2011, 9:41 PM CDT (02:41 UTC)
Expired: Jul 20, 2011, 12:30 AM CDT
In force: 3 hr
Issued by: NWS La Crosse, WI
Area: Storm-based polygon
Flood severity: None

County Clark County, WI

The radar

The La Crosse radar (KARX), 109 km from the middle of the area, began a volume at 02:41 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 00:00Z, 2.7 hours before the alert went out and 196 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1847 J/kg
Mixed-layer CIN: -24 J/kg
Mixed-layer LCL: 1140 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: 114 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.8

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

287 
WGUS53 KARX 200241
FFWARX
WIC019-200530-
/O.NEW.KARX.FF.W.0013.110720T0241Z-110720T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LA CROSSE WI
941 PM CDT TUE JUL 19 2011

THE NATIONAL WEATHER SERVICE IN LA CROSSE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CLARK COUNTY IN CENTRAL WISCONSIN...

* UNTIL 1230 AM CDT

* AT 939 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE      
  WARNED AREA. RAINFALL RATES OF 2 TO 3 INCHES PER HOUR HAVE BEEN    
  REPORTED WITH THESE STORMS.   

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  NEILLSVILLE...GREENWOOD...HUMBIRD...LOYAL AND SHORTVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. DO
NOT ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND TO
ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN
WATER BEGINS RISING.

&&

LAT...LON 4479 9032 4442 9032 4453 9092 4493 9092

$$

RABERDING

1 follow-up statement

415 
WGUS73 KARX 200320
FFSARX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
1020 PM CDT TUE JUL 19 2011

WIC019-200530-
/O.CON.KARX.FF.W.0013.000000T0000Z-110720T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK WI-
1020 PM CDT TUE JUL 19 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR CLARK COUNTY UNTIL 1230
AM CDT...

AT 1018 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. THE 
INTENSITY OF THE RAIN HAS DIMINISHED SOMEWHAT...WITH RATES AROUND 1 
TO 2 INCHES PER HOUR ACROSS SOUTHERN CLARK COUNTY. THE RAIN HAD 
DIMINISHED TO LIGHT TO MODERATE FURTHER NORTH ACROSS CENTRAL AND 
NORTHERN CLARK COUNTY.

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
NEILLSVILLE...GREENWOOD...HUMBIRD...LOYAL AND SHORTVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLOODING IS OBSERVED...ACT QUICKLY. DO NOT
ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND. DO NOT
STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

&&

LAT...LON 4479 9032 4442 9032 4453 9092 4493 9092

$$

RABERDING

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 19, 7:19 PM CDT	Tornado Warning	ARX	Clark, Taylor	26 min
Jul 19, 7:43 PM CDT	Tornado Warning	ARX	Clark, Taylor	32 min
Jul 19, 7:45 PM CDT	Severe Thunderstorm Warning	ARX	Clark, Taylor	60 min
Jul 19, 8:37 PM CDT	Flash Flood Warning	ARX	Clark, Taylor	4 hr
Jul 19, 8:45 PM CDT	Severe Thunderstorm Warning	ARX	Clark, Taylor	60 min
Jul 19, 9:45 PM CDT	Severe Thunderstorm Warning	ARX	Clark, Jackson, Trempealeau	60 min
Jul 19, 10:27 PM CDT	Severe Thunderstorm Warning	ARX	Adams, Juneau	63 min
Jul 20, 12:25 AM CDT	Areal Flood Warning	ARX	Clark, Taylor	9 hr

Nearby

Flash Flood Warnings in Wisconsin, 2011 Every flash flood warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.